1. Field of the Invention
The present invention relates to a heatsink for dissipating heat from electronic components, such as components of a computer system.
2. Description of the Related Art
Central processing units (CPUs), thermoelectric modules, power transistors, video graphics array (VGA) chips, radio frequency chips and the like are examples of electronic components. Since such electronic components produce a large amount of heat during operation, effective cooling is an important concern. If an electronic component is heated over a predetermined temperature, an error may occur in the electronic component, or the electronic component may become damaged. For this reason, heatsinks are installed on such electronic components and dissipate generated heat into the air, thus lowering the temperature of the electronic component.
The ideal heatsink effectively dissipating heat from an electronic component into the air is made of a material having a high thermal conductivity, has a short thermally conductive pathway, a large heat conducting area and a large heat-dissipating area, and allows a smooth air flow near the heat dissipating area. In order to satisfy these requirements, a conventional heatsink is made by extruding an aluminum (Al) alloy and cross-cutting the extrusion, or by die casting Al.
However, these two methods cannot be applied to some materials having a high thermal conductivity, for example, to copper (Cu) which has a higher thermal conductivity than Al alloy. Also, the conventional methods do not provide the heatsink with a sufficiently large heat dissipating area and heat conducting area, and with a short thermally conductive pathway.
U.S. Pat. No. 5,419,780 discloses a heatsink manufactured through extrusion and cross-cutting. Thus, a highly thermally conductive material cannot be used to manufacture the heatsink, and the heat conducting area and heat dissipating area of the heatsink are not large enough for effective heat transfer. Also, the thermally conductive pathway is long.
U.S. Pat. No. 5,509,465 discloses a heatsink in which a plurality of fins having a flange between each fin are overlapped. Although the heatsink has a large heat dissipating area, the heat conducting efficiency is low due to the long thermally conductive pathway, small heat conducting area, and the presence of a heat transfer boundary.
Such conventional heatsinks have high heat resistance and air must be forcibly circulated with the assistance of a fan for more effective heat transfer from the electronic component to the air. For example, in order to appropriately maintain the temperature of a CPU which produces heat at a rate of 15W or more, a fan must be installed near the heatsink mounted on the CPU to lower the heat resistance.
As set forth above, the conventional heatsink requires a fan for appropriate heat dissipation, which has the inherent problems of high power consumption, noises and scattering and sticking of dust. In particular, noise must be eliminated so that the user can work in a quiet environment. Also, with increases in the speed of CPUs, heat generation from CPUs has increased. However, heat generated by CPUs hinders speed increases of CPUs. Thus, the problem associated with the generation of heat in the CPU must be avoided for a high-speed CPU.